Arginine Feeding: a Novel Strategy to Improve Protein Metabolism in Cancer and the Response to Surgery

In the present proposal, the effects of surgery and cancer will be examined by comparing subjects undergoing breast surgery because of malignancy vs. prophylactic reasons (aim 1). Furthermore, the effects of one-week pre-operative protein feeding with or without enrichment with arginine on post-operative protein metabolism (aim 2) will be investigated in the cancer group. Variables of interest are: 1. Whole-body and skeletal muscle protein metabolism, whole body arginine turnover and de-novo arginine production rate, and the anabolic capacity to feeding(assessed by stable isotope methodology). 2. Body weight, muscle mass and functional status, score for well-being (assessed by Profile of Mood State and Mini Mental State). In the present study, we propose that a nutritional supplement that is high in protein content and enhanced in arginine will be more effective than a typical commercial nutritional supplement in diminishing the catabolic effects of surgery in subjects with cancer, thereby optimizing their quality of life. If this is found to be the case, this would provide the basis for reformulating the nutritional composition in accord with the effects of cancer and surgery on protein metabolism.